hill. the battle over gun control front and center today. former arizona congresswoman gabby giffords, who survived that mass shooting two years ago, appeared before the senate judiciary committee along with her husband, former astronaut mark kelly. he told the panel cushing gun violence is a complex problem. but he says that is no excuse for inaction. >> when dangerous people get dangerous guns we are all the more vulnerable. dangerous people with weapons specifically designed to inflict maximum lethality upon others have turned every single corner of our society into places of carnage and gross human loss. jon: our next guest is the committee's ranking republican. he agrees we need some common sense reform but warns of the need to proceed with caution. >> we should not rush to pass legislation that will not reduce mass killings. banning guns based on their appearance does not make sense. the 1994 assault weapons bandied not stop columbine. the justice department found the ban ineffective. scholars have indicated that refining or expanding such legislation will not cut gun violence.